Kyle was also surprised by his weight loss, admitting he's 'still guzzing soft drink' and 'doing nothing' after work.

The controversial presenter did, however, reveal he'd been cutting milk from his diet, having previously been drinking 'two litres' a day.

Offering his words of encouragement to Jackie, Kyle told the blonde: 'You can't make a judgement one week into a diet. You've got to pursue it.'

'This is so depressing': Jackie was disheartened by her co-star's weight loss, after revealing she'd been cutting out carbs and sugars all week

Earlier in the segment, Jackie told Kyle and their listeners about her new diet.

'I'm trying a new one - it's high in fat... I know it sounds bizarre but you cut out carbs and sugar, and fat is your friend,' Jackie said.

Jackie has previously been open about her quest for weight loss, often weighing herself on-air alongside Kyle.

Weight loss journey: The mother-of-one has previously been vocal about her quest to lose weight, even joining the station's 'Fat Club' last year (pictured in 2006)

'Fallen off the wagon': In August, the blonde beauty lamented about her bad eating habits, explaining she'd 'fallen off the wagon' after eating 'two bowls of macaroni and cheeseburgers' (pictured in 2009)

Last August, Jackie opened up about her eating habits after joining the station's 'Fat Club' in a bid to lose weight.

'I haven’t been able to get back on track because I have had two bowls of macaroni and cheeseburgers. I have fallen off the wagon,' she explained.

Kyle, who weighed 138kg at the time, replied: 'You haven't just fallen off the wagon, you have been dragged across the desert by a rope. This is a bad situation.'

'This is a bad situation': Jackie's co-host, who weighed 138kg at the time, didn't hold back while lecturing Jackie about her eating habits